xref: /freebsd/sys/dev/hid/hidbus.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019-2020 Vladimir Kondratyev <wulf@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/bus.h>
30 #include <sys/ck.h>
31 #include <sys/epoch.h>
32 #include <sys/kdb.h>
33 #include <sys/kernel.h>
34 #include <sys/libkern.h>
35 #include <sys/lock.h>
36 #include <sys/malloc.h>
37 #include <sys/module.h>
38 #include <sys/mutex.h>
39 #include <sys/proc.h>
40 #include <sys/sbuf.h>
41 #include <sys/sx.h>
42 #include <sys/systm.h>
43 
44 #define	HID_DEBUG_VAR	hid_debug
45 #include <dev/hid/hid.h>
46 #include <dev/hid/hidbus.h>
47 #include <dev/hid/hidquirk.h>
48 
49 #include "hid_if.h"
50 
51 #define	INPUT_EPOCH	global_epoch_preempt
52 #define	HID_RSIZE_MAX	1024
53 
54 static hid_intr_t	hidbus_intr;
55 
56 static device_probe_t	hidbus_probe;
57 static device_attach_t	hidbus_attach;
58 static device_detach_t	hidbus_detach;
59 
60 struct hidbus_ivars {
61 	int32_t				usage;
62 	uint8_t				index;
63 	uint32_t			flags;
64 	uintptr_t			driver_info;    /* for internal use */
65 	struct mtx			*mtx;		/* child intr mtx */
66 	hid_intr_t			*intr_handler;	/* executed under mtx*/
67 	void				*intr_ctx;
68 	unsigned int			refcnt;		/* protected by mtx */
69 	struct epoch_context		epoch_ctx;
70 	CK_STAILQ_ENTRY(hidbus_ivars)	link;
71 };
72 
73 struct hidbus_softc {
74 	device_t			dev;
75 	struct sx			sx;
76 	struct mtx			mtx;
77 
78 	bool				nowrite;
79 
80 	struct hid_rdesc_info		rdesc;
81 	bool				overloaded;
82 	int				nest;	/* Child attach nesting lvl */
83 	int				nauto;	/* Number of autochildren */
84 
85 	CK_STAILQ_HEAD(, hidbus_ivars)	tlcs;
86 };
87 
88 static int
89 hidbus_fill_rdesc_info(struct hid_rdesc_info *hri, const void *data,
90     hid_size_t len)
91 {
92 	int error = 0;
93 
94 	hri->data = __DECONST(void *, data);
95 	hri->len = len;
96 
97 	/*
98 	 * If report descriptor is not available yet, set maximal
99 	 * report sizes high enough to allow hidraw to work.
100 	 */
101 	hri->isize = len == 0 ? HID_RSIZE_MAX :
102 	    hid_report_size_max(data, len, hid_input, &hri->iid);
103 	hri->osize = len == 0 ? HID_RSIZE_MAX :
104 	    hid_report_size_max(data, len, hid_output, &hri->oid);
105 	hri->fsize = len == 0 ? HID_RSIZE_MAX :
106 	    hid_report_size_max(data, len, hid_feature, &hri->fid);
107 
108 	if (hri->isize > HID_RSIZE_MAX) {
109 		DPRINTF("input size is too large, %u bytes (truncating)\n",
110 		    hri->isize);
111 		hri->isize = HID_RSIZE_MAX;
112 		error = EOVERFLOW;
113 	}
114 	if (hri->osize > HID_RSIZE_MAX) {
115 		DPRINTF("output size is too large, %u bytes (truncating)\n",
116 		    hri->osize);
117 		hri->osize = HID_RSIZE_MAX;
118 		error = EOVERFLOW;
119 	}
120 	if (hri->fsize > HID_RSIZE_MAX) {
121 		DPRINTF("feature size is too large, %u bytes (truncating)\n",
122 		    hri->fsize);
123 		hri->fsize = HID_RSIZE_MAX;
124 		error = EOVERFLOW;
125 	}
126 
127 	return (error);
128 }
129 
130 int
131 hidbus_locate(const void *desc, hid_size_t size, int32_t u, enum hid_kind k,
132     uint8_t tlc_index, uint8_t index, struct hid_location *loc,
133     uint32_t *flags, uint8_t *id, struct hid_absinfo *ai)
134 {
135 	struct hid_data *d;
136 	struct hid_item h;
137 	int i;
138 
139 	d = hid_start_parse(desc, size, 1 << k);
140 	HIDBUS_FOREACH_ITEM(d, &h, tlc_index) {
141 		for (i = 0; i < h.nusages; i++) {
142 			if (h.kind == k && h.usages[i] == u) {
143 				if (index--)
144 					break;
145 				if (loc != NULL)
146 					*loc = h.loc;
147 				if (flags != NULL)
148 					*flags = h.flags;
149 				if (id != NULL)
150 					*id = h.report_ID;
151 				if (ai != NULL && (h.flags&HIO_RELATIVE) == 0)
152 					*ai = (struct hid_absinfo) {
153 					    .max = h.logical_maximum,
154 					    .min = h.logical_minimum,
155 					    .res = hid_item_resolution(&h),
156 					};
157 				hid_end_parse(d);
158 				return (1);
159 			}
160 		}
161 	}
162 	if (loc != NULL)
163 		loc->size = 0;
164 	if (flags != NULL)
165 		*flags = 0;
166 	if (id != NULL)
167 		*id = 0;
168 	hid_end_parse(d);
169 	return (0);
170 }
171 
172 bool
173 hidbus_is_collection(const void *desc, hid_size_t size, int32_t usage,
174     uint8_t tlc_index)
175 {
176 	struct hid_data *d;
177 	struct hid_item h;
178 	bool ret = false;
179 
180 	d = hid_start_parse(desc, size, 0);
181 	HIDBUS_FOREACH_ITEM(d, &h, tlc_index) {
182 		if (h.kind == hid_collection && h.usage == usage) {
183 			ret = true;
184 			break;
185 		}
186 	}
187 	hid_end_parse(d);
188 	return (ret);
189 }
190 
191 static device_t
192 hidbus_add_child(device_t dev, u_int order, const char *name, int unit)
193 {
194 	struct hidbus_softc *sc = device_get_softc(dev);
195 	struct hidbus_ivars *tlc;
196 	device_t child;
197 
198 	child = device_add_child_ordered(dev, order, name, unit);
199 	if (child == NULL)
200 			return (child);
201 
202 	tlc = malloc(sizeof(struct hidbus_ivars), M_DEVBUF, M_WAITOK | M_ZERO);
203 	tlc->mtx = &sc->mtx;
204 	device_set_ivars(child, tlc);
205 	sx_xlock(&sc->sx);
206 	CK_STAILQ_INSERT_TAIL(&sc->tlcs, tlc, link);
207 	sx_unlock(&sc->sx);
208 
209 	return (child);
210 }
211 
212 static int
213 hidbus_enumerate_children(device_t dev, const void* data, hid_size_t len)
214 {
215 	struct hidbus_softc *sc = device_get_softc(dev);
216 	struct hid_data *hd;
217 	struct hid_item hi;
218 	device_t child;
219 	uint8_t index = 0;
220 
221 	if (data == NULL || len == 0)
222 		return (ENXIO);
223 
224 	/* Add a child for each top level collection */
225 	hd = hid_start_parse(data, len, 1 << hid_input);
226 	while (hid_get_item(hd, &hi)) {
227 		if (hi.kind != hid_collection || hi.collevel != 1)
228 			continue;
229 		child = BUS_ADD_CHILD(dev, 0, NULL, -1);
230 		if (child == NULL) {
231 			device_printf(dev, "Could not add HID device\n");
232 			continue;
233 		}
234 		hidbus_set_index(child, index);
235 		hidbus_set_usage(child, hi.usage);
236 		hidbus_set_flags(child, HIDBUS_FLAG_AUTOCHILD);
237 		index++;
238 		DPRINTF("Add child TLC: 0x%04x:0x%04x\n",
239 		    HID_GET_USAGE_PAGE(hi.usage), HID_GET_USAGE(hi.usage));
240 	}
241 	hid_end_parse(hd);
242 
243 	if (index == 0)
244 		return (ENXIO);
245 
246 	sc->nauto = index;
247 
248 	return (0);
249 }
250 
251 static int
252 hidbus_attach_children(device_t dev)
253 {
254 	struct hidbus_softc *sc = device_get_softc(dev);
255 	int error;
256 
257 	HID_INTR_SETUP(device_get_parent(dev), dev, hidbus_intr, sc,
258 	    &sc->rdesc);
259 
260 	error = hidbus_enumerate_children(dev, sc->rdesc.data, sc->rdesc.len);
261 	if (error != 0)
262 		DPRINTF("failed to enumerate children: error %d\n", error);
263 
264 	/*
265 	 * hidbus_attach_children() can recurse through device_identify->
266 	 * hid_set_report_descr() call sequence. Do not perform children
267 	 * attach twice in that case.
268 	 */
269 	sc->nest++;
270 	bus_generic_probe(dev);
271 	sc->nest--;
272 	if (sc->nest != 0)
273 		return (0);
274 
275 	if (hid_is_keyboard(sc->rdesc.data, sc->rdesc.len) != 0)
276 		error = bus_generic_attach(dev);
277 	else
278 		error = bus_delayed_attach_children(dev);
279 	if (error != 0)
280 		device_printf(dev, "failed to attach child: error %d\n", error);
281 
282 	return (error);
283 }
284 
285 static int
286 hidbus_detach_children(device_t dev)
287 {
288 	device_t *children, bus;
289 	bool is_bus;
290 	int i, error;
291 
292 	error = 0;
293 
294 	is_bus = device_get_devclass(dev) == devclass_find("hidbus");
295 	bus = is_bus ? dev : device_get_parent(dev);
296 
297 	KASSERT(device_get_devclass(bus) == devclass_find("hidbus"),
298 	    ("Device is not hidbus or it's child"));
299 
300 	if (is_bus) {
301 		/* If hidbus is passed, delete all children. */
302 		bus_generic_detach(bus);
303 		device_delete_children(bus);
304 	} else {
305 		/*
306 		 * If hidbus child is passed, delete all hidbus children
307 		 * except caller. Deleting the caller may result in deadlock.
308 		 */
309 		error = device_get_children(bus, &children, &i);
310 		if (error != 0)
311 			return (error);
312 		while (i-- > 0) {
313 			if (children[i] == dev)
314 				continue;
315 			DPRINTF("Delete child. index=%d (%s)\n",
316 			    hidbus_get_index(children[i]),
317 			    device_get_nameunit(children[i]));
318 			error = device_delete_child(bus, children[i]);
319 			if (error) {
320 				DPRINTF("Failed deleting %s\n",
321 				    device_get_nameunit(children[i]));
322 				break;
323 			}
324 		}
325 		free(children, M_TEMP);
326 	}
327 
328 	HID_INTR_UNSETUP(device_get_parent(bus), bus);
329 
330 	return (error);
331 }
332 
333 static int
334 hidbus_probe(device_t dev)
335 {
336 
337 	device_set_desc(dev, "HID bus");
338 
339 	/* Allow other subclasses to override this driver. */
340 	return (BUS_PROBE_GENERIC);
341 }
342 
343 static int
344 hidbus_attach(device_t dev)
345 {
346 	struct hidbus_softc *sc = device_get_softc(dev);
347 	struct hid_device_info *devinfo = device_get_ivars(dev);
348 	void *d_ptr = NULL;
349 	hid_size_t d_len;
350 	int error;
351 
352 	sc->dev = dev;
353 	CK_STAILQ_INIT(&sc->tlcs);
354 	mtx_init(&sc->mtx, "hidbus ivar lock", NULL, MTX_DEF);
355 	sx_init(&sc->sx, "hidbus ivar list lock");
356 
357 	/*
358 	 * Ignore error. It is possible for non-HID device e.g. XBox360 gamepad
359 	 * to emulate HID through overloading of report descriptor.
360 	 */
361 	d_len = devinfo->rdescsize;
362 	if (d_len != 0) {
363 		d_ptr = malloc(d_len, M_DEVBUF, M_ZERO | M_WAITOK);
364 		error = hid_get_rdesc(dev, d_ptr, d_len);
365 		if (error != 0) {
366 			free(d_ptr, M_DEVBUF);
367 			d_len = 0;
368 			d_ptr = NULL;
369 		}
370 	}
371 
372 	hidbus_fill_rdesc_info(&sc->rdesc, d_ptr, d_len);
373 
374 	sc->nowrite = hid_test_quirk(devinfo, HQ_NOWRITE);
375 
376 	error = hidbus_attach_children(dev);
377 	if (error != 0) {
378 		hidbus_detach(dev);
379 		return (ENXIO);
380 	}
381 
382 	return (0);
383 }
384 
385 static int
386 hidbus_detach(device_t dev)
387 {
388 	struct hidbus_softc *sc = device_get_softc(dev);
389 
390 	hidbus_detach_children(dev);
391 	sx_destroy(&sc->sx);
392 	mtx_destroy(&sc->mtx);
393 	free(sc->rdesc.data, M_DEVBUF);
394 
395 	return (0);
396 }
397 
398 static void
399 hidbus_child_detached(device_t bus, device_t child)
400 {
401 	struct hidbus_softc *sc = device_get_softc(bus);
402 	struct hidbus_ivars *tlc = device_get_ivars(child);
403 
404 	KASSERT(tlc->refcnt == 0, ("Child device is running"));
405 	tlc->mtx = &sc->mtx;
406 	tlc->intr_handler = NULL;
407 	tlc->flags &= ~HIDBUS_FLAG_CAN_POLL;
408 }
409 
410 /*
411  * Epoch callback indicating tlc is safe to destroy
412  */
413 static void
414 hidbus_ivar_dtor(epoch_context_t ctx)
415 {
416 	struct hidbus_ivars *tlc;
417 
418 	tlc = __containerof(ctx, struct hidbus_ivars, epoch_ctx);
419 	free(tlc, M_DEVBUF);
420 }
421 
422 static void
423 hidbus_child_deleted(device_t bus, device_t child)
424 {
425 	struct hidbus_softc *sc = device_get_softc(bus);
426 	struct hidbus_ivars *tlc = device_get_ivars(child);
427 
428 	sx_xlock(&sc->sx);
429 	KASSERT(tlc->refcnt == 0, ("Child device is running"));
430 	CK_STAILQ_REMOVE(&sc->tlcs, tlc, hidbus_ivars, link);
431 	sx_unlock(&sc->sx);
432 	epoch_call(INPUT_EPOCH, hidbus_ivar_dtor, &tlc->epoch_ctx);
433 }
434 
435 static int
436 hidbus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
437 {
438 	struct hidbus_softc *sc = device_get_softc(bus);
439 	struct hidbus_ivars *tlc = device_get_ivars(child);
440 
441 	switch (which) {
442 	case HIDBUS_IVAR_INDEX:
443 		*result = tlc->index;
444 		break;
445 	case HIDBUS_IVAR_USAGE:
446 		*result = tlc->usage;
447 		break;
448 	case HIDBUS_IVAR_FLAGS:
449 		*result = tlc->flags;
450 		break;
451 	case HIDBUS_IVAR_DRIVER_INFO:
452 		*result = tlc->driver_info;
453 		break;
454 	case HIDBUS_IVAR_LOCK:
455 		*result = (uintptr_t)(tlc->mtx == &sc->mtx ? NULL : tlc->mtx);
456 		break;
457 	default:
458 		return (EINVAL);
459 	}
460 	return (0);
461 }
462 
463 static int
464 hidbus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
465 {
466 	struct hidbus_softc *sc = device_get_softc(bus);
467 	struct hidbus_ivars *tlc = device_get_ivars(child);
468 
469 	switch (which) {
470 	case HIDBUS_IVAR_INDEX:
471 		tlc->index = value;
472 		break;
473 	case HIDBUS_IVAR_USAGE:
474 		tlc->usage = value;
475 		break;
476 	case HIDBUS_IVAR_FLAGS:
477 		tlc->flags = value;
478 		if ((value & HIDBUS_FLAG_CAN_POLL) != 0)
479 			HID_INTR_SETUP(
480 			    device_get_parent(bus), bus, NULL, NULL, NULL);
481 		break;
482 	case HIDBUS_IVAR_DRIVER_INFO:
483 		tlc->driver_info = value;
484 		break;
485 	case HIDBUS_IVAR_LOCK:
486 		tlc->mtx = (struct mtx *)value == NULL ?
487 		    &sc->mtx : (struct mtx *)value;
488 		break;
489 	default:
490 		return (EINVAL);
491 	}
492 	return (0);
493 }
494 
495 /* Location hint for devctl(8) */
496 static int
497 hidbus_child_location(device_t bus, device_t child, struct sbuf *sb)
498 {
499 	struct hidbus_ivars *tlc = device_get_ivars(child);
500 
501 	sbuf_printf(sb, "index=%hhu", tlc->index);
502         return (0);
503 }
504 
505 /* PnP information for devctl(8) */
506 static int
507 hidbus_child_pnpinfo(device_t bus, device_t child, struct sbuf *sb)
508 {
509 	struct hidbus_ivars *tlc = device_get_ivars(child);
510 	struct hid_device_info *devinfo = device_get_ivars(bus);
511 
512 	sbuf_printf(sb, "page=0x%04x usage=0x%04x bus=0x%02hx "
513 	    "vendor=0x%04hx product=0x%04hx version=0x%04hx%s%s",
514 	    HID_GET_USAGE_PAGE(tlc->usage), HID_GET_USAGE(tlc->usage),
515 	    devinfo->idBus, devinfo->idVendor, devinfo->idProduct,
516 	    devinfo->idVersion, devinfo->idPnP[0] == '\0' ? "" : " _HID=",
517 	    devinfo->idPnP[0] == '\0' ? "" : devinfo->idPnP);
518 	return (0);
519 }
520 
521 void
522 hidbus_set_desc(device_t child, const char *suffix)
523 {
524 	device_t bus = device_get_parent(child);
525 	struct hidbus_softc *sc = device_get_softc(bus);
526 	struct hid_device_info *devinfo = device_get_ivars(bus);
527 	struct hidbus_ivars *tlc = device_get_ivars(child);
528 	char buf[80];
529 
530 	/* Do not add NULL suffix or if device name already contains it. */
531 	if (suffix != NULL && strcasestr(devinfo->name, suffix) == NULL &&
532 	    (sc->nauto > 1 || (tlc->flags & HIDBUS_FLAG_AUTOCHILD) == 0)) {
533 		snprintf(buf, sizeof(buf), "%s %s", devinfo->name, suffix);
534 		device_set_desc_copy(child, buf);
535 	} else
536 		device_set_desc(child, devinfo->name);
537 }
538 
539 device_t
540 hidbus_find_child(device_t bus, int32_t usage)
541 {
542 	device_t *children, child;
543 	int ccount, i;
544 
545 	bus_topo_assert();
546 
547 	/* Get a list of all hidbus children */
548 	if (device_get_children(bus, &children, &ccount) != 0)
549 		return (NULL);
550 
551 	/* Scan through to find required TLC */
552 	for (i = 0, child = NULL; i < ccount; i++) {
553 		if (hidbus_get_usage(children[i]) == usage) {
554 			child = children[i];
555 			break;
556 		}
557 	}
558 	free(children, M_TEMP);
559 
560 	return (child);
561 }
562 
563 void
564 hidbus_intr(void *context, void *buf, hid_size_t len)
565 {
566 	struct hidbus_softc *sc = context;
567 	struct hidbus_ivars *tlc;
568 	struct epoch_tracker et;
569 
570 	/*
571 	 * Broadcast input report to all subscribers.
572 	 * TODO: Add check for input report ID.
573 	 *
574 	 * Relock mutex on every TLC item as we can't hold any locks over whole
575 	 * TLC list here due to LOR with open()/close() handlers.
576 	 */
577 	if (!HID_IN_POLLING_MODE())
578 		epoch_enter_preempt(INPUT_EPOCH, &et);
579 	CK_STAILQ_FOREACH(tlc, &sc->tlcs, link) {
580 		if (tlc->refcnt == 0 || tlc->intr_handler == NULL)
581 			continue;
582 		if (HID_IN_POLLING_MODE()) {
583 			if ((tlc->flags & HIDBUS_FLAG_CAN_POLL) != 0)
584 				tlc->intr_handler(tlc->intr_ctx, buf, len);
585 		} else {
586 			mtx_lock(tlc->mtx);
587 			tlc->intr_handler(tlc->intr_ctx, buf, len);
588 			mtx_unlock(tlc->mtx);
589 		}
590 	}
591 	if (!HID_IN_POLLING_MODE())
592 		epoch_exit_preempt(INPUT_EPOCH, &et);
593 }
594 
595 void
596 hidbus_set_intr(device_t child, hid_intr_t *handler, void *context)
597 {
598 	struct hidbus_ivars *tlc = device_get_ivars(child);
599 
600 	tlc->intr_handler = handler;
601 	tlc->intr_ctx = context;
602 }
603 
604 static int
605 hidbus_intr_start(device_t bus, device_t child)
606 {
607 	MPASS(bus = device_get_parent(child));
608 	struct hidbus_softc *sc = device_get_softc(bus);
609 	struct hidbus_ivars *ivar = device_get_ivars(child);
610 	struct hidbus_ivars *tlc;
611 	bool refcnted = false;
612 	int error;
613 
614 	if (sx_xlock_sig(&sc->sx) != 0)
615 		return (EINTR);
616 	CK_STAILQ_FOREACH(tlc, &sc->tlcs, link) {
617 		refcnted |= (tlc->refcnt != 0);
618 		if (tlc == ivar) {
619 			mtx_lock(tlc->mtx);
620 			++tlc->refcnt;
621 			mtx_unlock(tlc->mtx);
622 		}
623 	}
624 	error = refcnted ? 0 : hid_intr_start(bus);
625 	sx_unlock(&sc->sx);
626 
627 	return (error);
628 }
629 
630 static int
631 hidbus_intr_stop(device_t bus, device_t child)
632 {
633 	MPASS(bus = device_get_parent(child));
634 	struct hidbus_softc *sc = device_get_softc(bus);
635 	struct hidbus_ivars *ivar = device_get_ivars(child);
636 	struct hidbus_ivars *tlc;
637 	bool refcnted = false;
638 	int error;
639 
640 	if (sx_xlock_sig(&sc->sx) != 0)
641 		return (EINTR);
642 	CK_STAILQ_FOREACH(tlc, &sc->tlcs, link) {
643 		if (tlc == ivar) {
644 			mtx_lock(tlc->mtx);
645 			MPASS(tlc->refcnt != 0);
646 			--tlc->refcnt;
647 			mtx_unlock(tlc->mtx);
648 		}
649 		refcnted |= (tlc->refcnt != 0);
650 	}
651 	error = refcnted ? 0 : hid_intr_stop(bus);
652 	sx_unlock(&sc->sx);
653 
654 	return (error);
655 }
656 
657 static void
658 hidbus_intr_poll(device_t bus, device_t child __unused)
659 {
660 	hid_intr_poll(bus);
661 }
662 
663 struct hid_rdesc_info *
664 hidbus_get_rdesc_info(device_t child)
665 {
666 	device_t bus = device_get_parent(child);
667 	struct hidbus_softc *sc = device_get_softc(bus);
668 
669 	return (&sc->rdesc);
670 }
671 
672 /*
673  * HID interface.
674  *
675  * Hidbus as well as any hidbus child can be passed as first arg.
676  */
677 
678 /* Read cached report descriptor */
679 int
680 hid_get_report_descr(device_t dev, void **data, hid_size_t *len)
681 {
682 	device_t bus;
683 	struct hidbus_softc *sc;
684 
685 	bus = device_get_devclass(dev) == devclass_find("hidbus") ?
686 	    dev : device_get_parent(dev);
687 	sc = device_get_softc(bus);
688 
689 	/*
690 	 * Do not send request to a transport backend.
691 	 * Use cached report descriptor instead of it.
692 	 */
693 	if (sc->rdesc.data == NULL || sc->rdesc.len == 0)
694 		return (ENXIO);
695 
696 	if (data != NULL)
697 		*data = sc->rdesc.data;
698 	if (len != NULL)
699 		*len = sc->rdesc.len;
700 
701 	return (0);
702 }
703 
704 /*
705  * Replace cached report descriptor with top level driver provided one.
706  *
707  * It deletes all hidbus children except caller and enumerates them again after
708  * new descriptor has been registered. Currently it can not be called from
709  * autoenumerated (by report's TLC) child device context as it results in child
710  * duplication. To overcome this limitation hid_set_report_descr() should be
711  * called from device_identify driver's handler with hidbus itself passed as
712  * 'device_t dev' parameter.
713  */
714 int
715 hid_set_report_descr(device_t dev, const void *data, hid_size_t len)
716 {
717 	struct hid_rdesc_info rdesc;
718 	device_t bus;
719 	struct hidbus_softc *sc;
720 	bool is_bus;
721 	int error;
722 
723 	bus_topo_assert();
724 
725 	is_bus = device_get_devclass(dev) == devclass_find("hidbus");
726 	bus = is_bus ? dev : device_get_parent(dev);
727 	sc = device_get_softc(bus);
728 
729 	/*
730 	 * Do not overload already overloaded report descriptor in
731 	 * device_identify handler. It causes infinite recursion loop.
732 	 */
733 	if (is_bus && sc->overloaded)
734 		return(0);
735 
736 	DPRINTFN(5, "len=%d\n", len);
737 	DPRINTFN(5, "data = %*D\n", len, data, " ");
738 
739 	error = hidbus_fill_rdesc_info(&rdesc, data, len);
740 	if (error != 0)
741 		return (error);
742 
743 	error = hidbus_detach_children(dev);
744 	if (error != 0)
745 		return(error);
746 
747 	/* Make private copy to handle a case of dynamicaly allocated data. */
748 	rdesc.data = malloc(len, M_DEVBUF, M_ZERO | M_WAITOK);
749 	bcopy(data, rdesc.data, len);
750 	sc->overloaded = true;
751 	free(sc->rdesc.data, M_DEVBUF);
752 	bcopy(&rdesc, &sc->rdesc, sizeof(struct hid_rdesc_info));
753 
754 	error = hidbus_attach_children(bus);
755 
756 	return (error);
757 }
758 
759 static int
760 hidbus_get_rdesc(device_t dev, device_t child __unused, void *data,
761     hid_size_t len)
762 {
763 	return (hid_get_rdesc(dev, data, len));
764 }
765 
766 static int
767 hidbus_read(device_t dev, device_t child __unused, void *data,
768     hid_size_t maxlen, hid_size_t *actlen)
769 {
770 	return (hid_read(dev, data, maxlen, actlen));
771 }
772 
773 static int
774 hidbus_write(device_t dev, device_t child __unused, const void *data,
775     hid_size_t len)
776 {
777 	struct hidbus_softc *sc;
778 	uint8_t id;
779 
780 	sc = device_get_softc(dev);
781 	/*
782 	 * Output interrupt endpoint is often optional. If HID device
783 	 * does not provide it, send reports via control pipe.
784 	 */
785 	if (sc->nowrite) {
786 		/* try to extract the ID byte */
787 		id = (sc->rdesc.oid & (len > 0)) ? *(const uint8_t*)data : 0;
788 		return (hid_set_report(dev, data, len, HID_OUTPUT_REPORT, id));
789 	}
790 
791 	return (hid_write(dev, data, len));
792 }
793 
794 static int
795 hidbus_get_report(device_t dev, device_t child __unused, void *data,
796     hid_size_t maxlen, hid_size_t *actlen, uint8_t type, uint8_t id)
797 {
798 	return (hid_get_report(dev, data, maxlen, actlen, type, id));
799 }
800 
801 static int
802 hidbus_set_report(device_t dev, device_t child __unused, const void *data,
803     hid_size_t len, uint8_t type, uint8_t id)
804 {
805 	return (hid_set_report(dev, data, len, type, id));
806 }
807 
808 static int
809 hidbus_set_idle(device_t dev, device_t child __unused, uint16_t duration,
810     uint8_t id)
811 {
812 	return (hid_set_idle(dev, duration, id));
813 }
814 
815 static int
816 hidbus_set_protocol(device_t dev, device_t child __unused, uint16_t protocol)
817 {
818 	return (hid_set_protocol(dev, protocol));
819 }
820 
821 static int
822 hidbus_ioctl(device_t dev, device_t child __unused, unsigned long cmd,
823     uintptr_t data)
824 {
825 	return (hid_ioctl(dev, cmd, data));
826 }
827 
828 /*------------------------------------------------------------------------*
829  *	hidbus_lookup_id
830  *
831  * This functions takes an array of "struct hid_device_id" and tries
832  * to match the entries with the information in "struct hid_device_info".
833  *
834  * Return values:
835  * NULL: No match found.
836  * Else: Pointer to matching entry.
837  *------------------------------------------------------------------------*/
838 const struct hid_device_id *
839 hidbus_lookup_id(device_t dev, const struct hid_device_id *id, int nitems_id)
840 {
841 	const struct hid_device_id *id_end;
842 	const struct hid_device_info *info;
843 	int32_t usage;
844 	bool is_child;
845 
846 	if (id == NULL) {
847 		goto done;
848 	}
849 
850 	id_end = id + nitems_id;
851 	info = hid_get_device_info(dev);
852 	is_child = device_get_devclass(dev) != devclass_find("hidbus");
853 	if (is_child)
854 		usage = hidbus_get_usage(dev);
855 
856 	/*
857 	 * Keep on matching array entries until we find a match or
858 	 * until we reach the end of the matching array:
859 	 */
860 	for (; id != id_end; id++) {
861 
862 		if (is_child && (id->match_flag_page) &&
863 		    (id->page != HID_GET_USAGE_PAGE(usage))) {
864 			continue;
865 		}
866 		if (is_child && (id->match_flag_usage) &&
867 		    (id->usage != HID_GET_USAGE(usage))) {
868 			continue;
869 		}
870 		if ((id->match_flag_bus) &&
871 		    (id->idBus != info->idBus)) {
872 			continue;
873 		}
874 		if ((id->match_flag_vendor) &&
875 		    (id->idVendor != info->idVendor)) {
876 			continue;
877 		}
878 		if ((id->match_flag_product) &&
879 		    (id->idProduct != info->idProduct)) {
880 			continue;
881 		}
882 		if ((id->match_flag_ver_lo) &&
883 		    (id->idVersion_lo > info->idVersion)) {
884 			continue;
885 		}
886 		if ((id->match_flag_ver_hi) &&
887 		    (id->idVersion_hi < info->idVersion)) {
888 			continue;
889 		}
890 		if (id->match_flag_pnp &&
891 		    strncmp(id->idPnP, info->idPnP, HID_PNP_ID_SIZE) != 0) {
892 			continue;
893 		}
894 		/* We found a match! */
895 		return (id);
896 	}
897 
898 done:
899 	return (NULL);
900 }
901 
902 /*------------------------------------------------------------------------*
903  *	hidbus_lookup_driver_info - factored out code
904  *
905  * Return values:
906  *    0: Success
907  * Else: Failure
908  *------------------------------------------------------------------------*/
909 int
910 hidbus_lookup_driver_info(device_t child, const struct hid_device_id *id,
911     int nitems_id)
912 {
913 
914 	id = hidbus_lookup_id(child, id, nitems_id);
915 	if (id) {
916 		/* copy driver info */
917 		hidbus_set_driver_info(child, id->driver_info);
918 		return (0);
919 	}
920 	return (ENXIO);
921 }
922 
923 const struct hid_device_info *
924 hid_get_device_info(device_t dev)
925 {
926 	device_t bus;
927 
928 	bus = device_get_devclass(dev) == devclass_find("hidbus") ?
929 	    dev : device_get_parent(dev);
930 
931 	return (device_get_ivars(bus));
932 }
933 
934 static device_method_t hidbus_methods[] = {
935 	/* device interface */
936 	DEVMETHOD(device_probe,		hidbus_probe),
937 	DEVMETHOD(device_attach,	hidbus_attach),
938 	DEVMETHOD(device_detach,	hidbus_detach),
939 	DEVMETHOD(device_suspend,	bus_generic_suspend),
940 	DEVMETHOD(device_resume,	bus_generic_resume),
941 
942 	/* bus interface */
943 	DEVMETHOD(bus_add_child,	hidbus_add_child),
944 	DEVMETHOD(bus_child_detached,	hidbus_child_detached),
945 	DEVMETHOD(bus_child_deleted,	hidbus_child_deleted),
946 	DEVMETHOD(bus_read_ivar,	hidbus_read_ivar),
947 	DEVMETHOD(bus_write_ivar,	hidbus_write_ivar),
948 	DEVMETHOD(bus_child_pnpinfo,	hidbus_child_pnpinfo),
949 	DEVMETHOD(bus_child_location,	hidbus_child_location),
950 
951 	/* hid interface */
952 	DEVMETHOD(hid_intr_start,	hidbus_intr_start),
953 	DEVMETHOD(hid_intr_stop,	hidbus_intr_stop),
954 	DEVMETHOD(hid_intr_poll,	hidbus_intr_poll),
955 	DEVMETHOD(hid_get_rdesc,	hidbus_get_rdesc),
956 	DEVMETHOD(hid_read,		hidbus_read),
957 	DEVMETHOD(hid_write,		hidbus_write),
958 	DEVMETHOD(hid_get_report,	hidbus_get_report),
959 	DEVMETHOD(hid_set_report,	hidbus_set_report),
960 	DEVMETHOD(hid_set_idle,		hidbus_set_idle),
961 	DEVMETHOD(hid_set_protocol,	hidbus_set_protocol),
962 	DEVMETHOD(hid_ioctl,		hidbus_ioctl),
963 
964 	DEVMETHOD_END
965 };
966 
967 driver_t hidbus_driver = {
968 	"hidbus",
969 	hidbus_methods,
970 	sizeof(struct hidbus_softc),
971 };
972 
973 MODULE_DEPEND(hidbus, hid, 1, 1, 1);
974 MODULE_VERSION(hidbus, 1);
975 DRIVER_MODULE(hidbus, atopcase, hidbus_driver, 0, 0);
976 DRIVER_MODULE(hidbus, hvhid, hidbus_driver, 0, 0);
977 DRIVER_MODULE(hidbus, iichid, hidbus_driver, 0, 0);
978 DRIVER_MODULE(hidbus, usbhid, hidbus_driver, 0, 0);
979